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linux-stable/tools/perf/arch/arm/util/Build

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perf tools: Avoid 'sample_reg_masks' being const + weak Being const + weak breaks with some compilers that constant-propagate from the weak symbol. This behavior is outside of the specification, but in LLVM is chosen to match GCC's behavior. LLVM's implementation was set in this patch: https://github.com/llvm/llvm-project/commit/f49573d1eedcf1e44893d5a062ac1b72c8419646 A const + weak symbol is set to be weak_odr: https://llvm.org/docs/LangRef.html ODR is one definition rule, and given there is one constant definition constant-propagation is possible. It is possible to get this code to miscompile with LLVM when applying link time optimization. As compilers become more aggressive, this is likely to break in more instances. Move the definition of sample_reg_masks to the conditional part of perf_regs.h and guard usage with HAVE_PERF_REGS_SUPPORT. This avoids the weak symbol. Fix an issue when HAVE_PERF_REGS_SUPPORT isn't defined from patch v1. In v3, add perf_regs.c for architectures that HAVE_PERF_REGS_SUPPORT but don't declare sample_regs_masks. Further notes: Jiri asked: "Is this just a precaution or you actualy saw some breakage?" Ian answered: "We saw a breakage with clang with thinlto enabled for linking. Our compiler team had recently seen, and were surprised by, a similar issue and were able to dig out the weak ODR issue." Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: clang-built-linux@googlegroups.com Cc: Guo Ren <guoren@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: linux-riscv@lists.infradead.org Cc: Mao Han <han_mao@c-sky.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20191001003623.255186-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-10-01 00:36:23 +00:00
perf-y += perf_regs.o
perf tools: Rename build libperf to perf Rename build libperf to perf, because it's used to build perf. The libperf build object name will be used for libperf library. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20190213123246.4015-4-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-13 12:32:39 +00:00
perf-$(CONFIG_DWARF) += dwarf-regs.o
perf build: Add arch arm objects building Move the arm arch objects building under build framework to be included in the libperf build object. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Tested-by: Will Deacon <will.deacon@arm.com> Cc: Alexis Berlemont <alexis.berlemont@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-7bxhmeh4bjabqsmxu4gl6p0b@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-12-30 13:07:04 +00:00
perf tools: Rename build libperf to perf Rename build libperf to perf, because it's used to build perf. The libperf build object name will be used for libperf library. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20190213123246.4015-4-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-13 12:32:39 +00:00
perf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
perf tools: Make coresight PMU listable Adding the required mechanic allowing 'perf list pmu' to discover coresight ETM/PTM tracers. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1474041004-13956-3-git-send-email-mathieu.poirier@linaro.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-16 15:49:59 +00:00
perf tools: Rename build libperf to perf Rename build libperf to perf, because it's used to build perf. The libperf build object name will be used for libperf library. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20190213123246.4015-4-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-13 12:32:39 +00:00
perf-$(CONFIG_AUXTRACE) += pmu.o auxtrace.o cs-etm.o
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